Concern over the ability of the United States to sustain the global economy as most of the world slows will be high on the agenda as the Group of 20 leading economies hold talks in Istanbul on Monday and Tuesday.

The meetings come as Greece casts a new shadow over Europe, cheap oil plays havoc with inflation and growth forecasts and a strengthening dollar threatens emerging economies.

“There is a lot at stake,” IMF Managing Director Christine Lagarde said in a blog post on Friday. “Without action, we could see the global economic supertanker continuing to be stuck in the shallow waters of sub-par growth and meagre job creation.”

Turkey’s Deputy Prime Minister Ali Babacan told an Institute of International Finance (IIF) meeting on Sunday that tackling sluggish global growth and giving low income nations more voice will be among the priorities for Turkey’s G20 presidency.

The former will be easier said than done.

U.S. Treasury Secretary Jack Lew said last week the United States could not be “the sole engine of growth” and a senior U.S. official said Washington’s message going into the meetings would again be that Europe is not doing enough.

World financial leaders agreed last year to launch new measures to raise their collective gross domestic product growth over the next five years and create millions of new jobs.

The pledge, called the Brisbane Action Plan, entails about 1,000 commitments. European officials said leaders in Istanbul were likely to agree to focus down to just 5-10 priorities per country to make them easier to monitor.

“Kick-starting global growth will be front and centre” at the G20 meetings, Canadian Finance Minister Joe Oliver said last week, citing the stalled euro zone, slowdowns in China and India and geopolitical crises in Ukraine, Iraq and Syria as key risks.

“Though America is carrying the world economy at the moment, that is simply not sustainable,” he added.

Germany is likely to argue that its rising domestic demand and plans to increase public spending show Europe’s largest economy is doing what it can, according to European sources familiar with the G20 agenda.

DELICATE BALANCE

Babacan said pushing G20 members to meet previous reform commitments would be key, a strategy he has dubbed: “Keep your word, or explain”.

“It has a lot to do with leadership ... Doing the necessary but difficult things,” he said.

Coming good on pledges made at November’s G20 summit in Brisbane could add more than $2 trillion to the global economy and create millions of new jobs over the next four years, Lagarde said in her blog post.

UBS Chairman Axel Weber said enabling the private sector to help close the financing gap for an estimated $60-70 trillion in infrastructure spending needed by 2030 would fuel growth.

Higher capital requirements are limiting banks’ ability to invest and regulators should “revisit whether they got that calibration right”, the former Bundesbank president told the IIF meeting.

“My key message to policymakers would be very easy -- don’t work against the private sector, work with it,” he said.

The G20 put together a global stimulus package during the 2007-09 financial crisis but today’s challenge is more delicate, with diverging monetary policies a cause of global turbulence.

The U.S. Federal Reserve looks set to raise interest rates this year, a stark contrast to impromptu cuts from India to Australia, Canada to Denmark, as well as China’s cut in bank reserve requirements and the abrupt end to the Swiss franc cap.

A senior Canadian official said the G20 communique would probably emphasise the importance of central bank actions in sustaining demand and said the Fed and Bank of England had voiced support for other central banks’ actions to lift growth.

Turkey’s own monetary policy may also be in the spotlight. Its central bank is under government pressure to cut interest rates ahead of a June election despite stubborn inflation, with critical comments by President Tayyip Erdogan last week sending the lira to a record low.

Erdogan renewed his criticism of the central bank on Sunday, saying it would be “held to account” if it failed to manage the lira’s exchange rate against a strengthening dollar.

A source close to French Finance Minister Michel Sapin said Greece would be discussed, although the situation was very different to a few years ago, with protection mechanisms in place and European markets less sensitive to its woes.

France has also asked to discuss the fight against terrorist financing, an important topic for Turkey given fighting with Islamic State militants taking place just over its southern borders in Syria and Iraq. (Additional reporting by Jan Strupczewski and Ece Toksabay in Istanbul, Jason Lange in Washington, Randall Palmer and David Ljunggren in Ottawa, Jean-Baptiste Vey in Paris, Gernot Heller in Berlin; Writing by Nick Tattersall; Editing by Catherine Evans and Stephen Powell)